In the UMTS (Universal Mobile Telecommunications System) network, the specifications of long term evolution (LTE) have been drafted for the purpose of further increasing high speed data rates, providing lower latency and so on (see non-patent literature 1). Also, the specifications of LTE-A (also referred to as “LTE-advanced,” “LTE Rel. 10,” “LTE Rel. 11” or “LTE Rel. 12”) have been drafted for further broadbandization and increased speed beyond LTE (also referred to as “LTE Rel. 8” or “LTE Rel. 9”), and successor systems of LTE (also referred to as, for example, “FRA (Future Radio Access),” “5G (5th generation mobile communication system),” “NR (New Radio),” “NX (New radio access),” “FX (Future generation radio access),” “LTE Rel. 13,” “LTE Rel. 14,” “LTE Rel. 15” and/or later versions) are under study.
In existing LTE systems (for example, LTE Rel. 8 to 13), downlink (DL) and/or uplink (UL) communication are performed using 1-ms subframes (also referred to as “transmission time intervals (TTIs)” and so on). These subframes are the time unit for transmitting one channel-encoded data packet, and serve as the unit of processing in, for example, scheduling, link adaptation, retransmission control (HARQ: Hybrid Automatic Repeat reQuest) and so on.
Also, in existing LTE systems (for example, LTE Rel. 8 to 13), a user terminal (UE: User Equipment) transmits uplink control information (UCI) by using uplink control channels (for example, PUCCH: Physical Uplink Control CHannel) and/or uplink data channels (for example, PUSCH: Physical Uplink Shared CHannel). The format of these uplink controls channel is referred to as “PUCCH format” and so on.
UCI includes at least one of a scheduling request (SR), retransmission control information in response to DL data (DL data channel (PDSCH: Physical Downlink Shared CHannel)) (also referred to as “HARQ-ACK (Hybrid Automatic Repeat reQuest-Acknowledgement),” “ACK,” “NACK (Negative ACK)” and so on) and channel state information (CSI).